It’s possible  to build a long-standing relationship with seller (holder of the seller carry-back note).

In my layman's understanding, a suitor won't be able to get "ahead" of the first position lien holder. 

Voucher holders shop for new rentals earlier than private renters and the inspection process takes a while. 

Side note: We are currently outside the US due to us not being able to get back for past 4 months due to Coronavirus as travel ban (we are on visas) means we can't enter country so trying to do this remotely so we can be good to go once we return.

I have read that (among other problems) if there is an underlying mortgage (ie seller isn't free and clear) the holder of that mortgage can demand full payment if a land contract is enacted.That pretty much undermines that entire reason for the land contract...since now the buyer would once again need financing to retain the property...As I said, there are other problems, but this one seems to be the most likely to occur and the most damaging.Thoughts?

The best part about doing a non HAFA short sale is that a good negotiator can deal with the second mortgage holder and not leave you stuck with doing that yourself.

I'm a long term holder myself.

This is generally the redemption right that most people are referring to when they discuss redemption rights vis-a-vis foreclosure.It looks like Alabama updated their redemption laws recently:http://alisondb.legislature.state.al.us/ALISON/SearchableInstruments/2018RS/PrintFiles/HB90-int.pdfAs in most redemption scenarios, the most junior lienors are able to redeem from the most senior, but must pay the debts of the most senior in order to redeem.In Alabama, it appears that a transfer of the right of redemption also effectuates the transfer of the interests of the party (the naked right of redemption cannot be separated from the underlying interest): (5) Any transferee of the interests of the debtor or mortgagor, either before or after the sale.

In addition the certificate holder can also bid on the property and if the bid is highest wins the bid and receives a Tax Deed. 

The mortgage holder didn't bat an eye.